Fluid control device and a fire protection system incorporating said device

ABSTRACT

A fluid control device in which a body member has a passage therethrough extending between an inlet adapted to be connected to a source fluid under pressure and an outlet adapted to be connected to a head for discharging the fluid. A control unit is supported by the body member and includes a movable member normally blocking the passage and having one side exposed to the fluid pressure in the passage. A closed chamber is provided and contains a pressurized gas which normally forces the movable member into the passage blocking position, with the movable member being adapted to move from the passage blocking position in response to the fluid pressure in the passage exceeding a predetermined value sufficient to overcome the force of the pressurized gas in the chamber, to permit the fluid in the passage to flow to the head for discharge.

ilnited States Patent [1 1 Livingston 1 FLUID CONTROL DEVICE AND A FIRE PROTECTION SYSTEM INCORPORATING SAID DEVICE [75] Inventor: William L. Livingston, Sharon,

Mass.

[73] Assignee: Factory Mutual Research Corporation, Norwood, Mass.

221 Filed: Mar. 4, 1974 21 Appl. No.: 447,673

[ Mar. 18,1975

Primary Examiner-M. Henson Wood, Jr. Assistant E.\'aminer-Michael Mar Attorney, Agent, or FirmLane, Aitken, Dunner & Ziems [57] ABSTRACT A fluid control device in which a body member has a passage therethrough extending between an inlet adapted to be connected to a source fluid under pressure and an outlet adapted to be connected to a head for discharging the fluid. A control unit is supported by the body member and includes a movable member normally blocking the passage and having one side exposed to the fluid pressure in the passage. A closed chamber is provided and contains a pressurized gas which normally forces the movable member into the passage blocking position, with the movable member being adapted to move from the passage blocking position in response to the fluid pressure in the passage exceeding a predetermined value sufficient to overcome the force of the pressurized gas in the chamber, to permit the fluid in the passage to flow to the head for discharge.

4 Claims, 2 Drawing Figures FLUID CONTROL DEVICE AND A FIRE PROTECTION SYSTEM INCORPORATING SAID DEVICE BACKGROUND OF THE INVENTION This invention relates to a fluid control device and a fire protection system incorporating a plurality of such devices and, more particularly, to such a device and system in which the flow of fluid is controlled in response to the pressure of the fluid.

The fire fighting capability of typical prior art fire protection systems employing a number of discharge heads mounted in an elevated position in the enclosure to be protected is often curtailed when the system is installed in relatively large storage facilities, such as warehouses, etc. One of the reasons for this is due to the fact that these large storage enclosures often contain very high stacks of combustible materials which frequently are highly inflammable. As a result, upon the development of fire in the enclosure, fire plumes or columns of feet and higher may flare out beneath the ceiling of the enclosure and actuate numerous heads located at such a distance from the fire that they are ineffective to deliver water or other extinguishant to the surfaces of the combustible materials. This contributes not only to redundant and flooding use of the water, but, more significantly, robs water from the heads over the fire where it is needed to extinguish the fire.

In U.S. Pat. No. 3,653,444 issued to the same inventor and assigned to the same assignee as the present application, a fixed fire extinguishing system is disclosed which is designed to limit the number of heads which will be activiated by a fire. With this arrangement, the first head actuated by the fire has a much better possibility of extinguishing the fire, because of the ability to retain a predetermined discharge density. If the heat of the fire spreads, additional heads are actuated to help the first head fight the fire and to wet down areas surrounding the fire to provide exposure protection to inhibit the spread of the fire. However, the additional heads which are allowed to be actuated are limited to a small predetermined number to avoid the prior art problems created by too many heads being actuated; namely, interfering with the fire fighting capabilities of those heads positioned immediately above the fire and over the area immediately surrounding the fire by reducing the discharge density, and causing unnecessary water damage by allowing an excessive number of heads to be actuated at points remote from the fire.

In accordance with a preferred embodiment of the above-mentioned application, the above is achieved by establishing a pressure floor so that a minimum pressure must exist at each head before it will open. The system is designed so that this minimum pressure will not be reached until a predetermined number of heads have been opened.

Although this arrangement resulted in a more efficient fire-fighting capability, it is relatively expensive due to the fact that each head had to be specially constructed to incorporate the pressure floor feature.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a fluid control device which can be adapted to existing systems using standard discharge heads, and, therefore, eliminate the costs involved in custom designing the heads, while providing an effective pressure floor system.

It is a further object of the present invention to provide a complete fire protection system incorporating a plurality of the above-mentioned fluid control devices.

Toward the fulfillment of these and other objects, the device of the present invention comprises a body having a passage therethrough between an inlet adapted to be connected to a source of fluid under pressure and an outlet adapted to be connected to a head for discharging said fluid, a movable member normally blocking said passage and having one side exposed to fluid pressure in said passage, and means including said movable member for defining a closed chamber for containing a pressurized fluid, said pressurized fluid normally forcing said movable member into said passage blocking position, said movable member adapted to move from said passage blocking position in response to the fluid pressure in said passage exceeding a predetermined value sufficient toovercome the force of said fluid in said chamber, to permit the fluid in said passage to flow to said head for discharge.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical cross-sectional view ofa fluid control device constructed according to the present invention; and

FIG. 2 is a partial, elevational view depicting a fire protection system incorporating a plurality of the fluid control devices of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring specifically to FIG. 1 of the drawings, the reference numeral 10 refers in general to the flow control device of the present invention which consists of a housing 12 having a passage 14 extending therethrough from an inlet opening 14a to an outlet opening 14b. That portion of the housing 12 defining the inlet opening 14a of the passage 14 is externally threaded, as shown at 16, while a portion of the inner surface of the passage 14 adjacent the outlet'opening 14b is internally threaded, as shown at 18.

A chamber 20 is formed in the housing 12 in communication with the passage 14 and receives a flow control unit shown in general by the reference numeral 22. The unit 22 is formed by a hollow central portion 24 having two hollow stem portions 26 and 28 extending from opposite sides thereof. The stem portions 26 and 28 extend through openings 30 and 32 formed in the housing 12, with the free end portions of each stem portion projecting slightly outwardly from the housing 12.

The central portion 24 of the flow control unit 22 is defined in part by a slightly flexible, disc-like member 34 which is adapted to move from an expanded position shown by the solid lines in FIG. 1 in which it is of a substantially semispherical shape, to a retracted position shown by the dashed lines in which it takes a substantially concave shape. In its expanded condition, the movable member 34 seats against a seal ring 36 disposed within a cut-out shoulder portion in the interior surface of the housing 12, to seal off the flow of fluid through the passage 14. In the retracted position of the movable member 34, the seal is broken and fluid can flow from the inlet opening 14a, through the upper portion of the passage 14 as viewed in FIG. 1, through the chamber 20 and the lower portion of the passage 14 to the outlet opening 14b, as shown by. the dashed arrows,

The flow control unit 22 contains a pressurized fluid, such as gas, which exerts an upwardly directed force against the movable member 34 to urge it upwardly against the seal ring 36 to prevent the flow of fluid through the passage 14. However, this force is selected so as to be less than the downwardly directed force against the movable member 34 caused by a predetermined fluid supply pressure which can be attained in the upper portion of the passage 14. As a result, the movable member 34 will move to its retracted position in response to the pressure of the fluid in the upper portion of the chamber 14 attaining or exceeding this predetermined value, to permit the flow of fluid through the passage 14.

A tip 40 of a fusible material is formed on the end of each stem 26 and 28 of the flow control unit 22. The tips 40 normally seal the pressurized gas in the flow control unit 22 and are adapted to melt at a predetermined temperature to permit the release of the pressurized gas from the unit for reasons that will be described in detail later.

In operation, the externally threaded portion 16 of the housing 12 is connected to a conduit system, or the like, via an internally threaded T-connector, shown partially by the reference numeral 42, for supplying fluid, such as water, to the inlet 14a of the housing. An externally threaded portion of a discharge head, shown partially by the reference numeral 44, is threadedly engaged with the threaded portion 18 of the housing 12 to discharge the water after it passes through the passage 14. I

Assuming the water pressure in the upper portion of the passage 14 acting on the movable member 34 of the flow control unit 22 is less than a predetermined value, the pressurized gas in the latter unit will force the member 34 upwardly into a sealing engagement with the seal ring 36 thus preventing the flow of water through the housing 12. However, if the water pressure in the system rises to a value sufficient to force the movable member 34 downwardly to the position shown by the dashed lines against the force of the pressurized gas, the water will pass into the chamber 20 and outwardly through the outlet 14b, where it is discharged through the head 44.

In the event the water pressure in the system later drops below the above-mentioned predetermined value, the pressurized gas within the flow control unit 22 will again force the movable member 34 upwardly against the seal ring 36 to prevent any additional flow of fluid through the passage 14.

If the temperature in the vicinity of the body member 12 is sufficient to melt either fusible tip 40, the pressurized gas in the flow control unit 22 will be allowed to escape, the movable member 34 will move downwardly under the force of the water, regardless of the latters pressure, and the water will flow through the housing 12 for discharge from the head 44.

It is understood that a fusible link may also be provided on the head 44 to control its operation, with the temperature required to actuate the latter link normally being less than that required to melt the fusible tips so that the latter provide a fail-safe type of temperature override.

FIG. 2 depicts the control devices 10 of the present invention incorporated in a fire protection system shown installed in a space shown in general by the reference numeral 50.In particular, a pair of branch lines 52 are supported in an elevated position in the space 50 and extend to either side of a crossmain shown in section by the reference numeral 54, with a plurality of the T-connectors 42 extending downwardly at spaced intervals along each branch line 52. Each control device 10 is connected to the pendant portion of a T- connector 42 and receives a discharge head- 44, with the connections being made in the manner described above.

The heads 44 have been shown, for the purpose of example, in the form of direct discharge nozzles disposed directly over a plurality of materials A-F to be protected from tire, and are more specifically disclosed in applicants US. Pat. No. 3,743,022, also assigned to the assignee of the present invention. Alternatively, the heads 58 can be in the form of conventional sprinkler heads in which the water is discharged against a serrated disc to create a mist-type spray pattern in a wellknown manner.

Other variations of the specific construction and arrangement of the flow control device and the fire protection system disclosed above can be made by those skilled in the art without departing from the invention as defined in the appended claims.

I claim:

1. A fluid control device comprising a body having a passage therethrough between an inlet adapted to be connected to a source of fluid under pressure and an outlet adapted to be connected to a head for discharging said fluid; a movable member normally blocking said passage and having one side exposed to fluid pressure in said passage; means including said movable member for defining a closed chamber for containing a pressurized fluid, said pressurized fluid normally forcing said movable member into said passage blocking position, said movable member adapted to move from said passage blocking position in response to the fluid pressure in said passage exceeding a predetermined value sufficient to overcome the force of said fluid in said chamber, to permit the fluid in said passage to flow to said head for discharge; and means responsive to the presence of a predetermined temperature in the vicinity of said body member to permit the escape of said fluid from said chamber and permit said movable member to be forced from said passage blocking position by the fluid in said passage, regardless of the pressure of said latterrfluid.

2. The device of claim 1 wherein said movable member is adapted to move back to said passage blocking position in response to the fluid pressure in said passage dropping below said predetermined value.

3. A fire protection system comprising conduit means disposed in a space to be protected from fire and adapted to be connected to a source of extinguishant, a body member connected to said conduit means and having a passage therethrough between an inlet registering with said conduit means and an outlet, a discharge head connected to said outlet for discharging said fluid; a movable member normally blocking said passage and having one side exposed to said extinguishant in said passage; means including said movable member for defining a closed chamber for containing predetermined value sufficient to overcome the force of said fluid in said chamber to permit the fluid in said passage to flow to said head for discharge; and means responsive to the presence of a predetermined temperblocking position by the extinguishant in said passage, regardless of the pressure of said latter fluid.

4. The system of claim 3 wherein said movable member is adapted to move back to said passage blocking ature in the vicinity of said body member to permit the 5 position in response to the fluid pressure in said passage dropping below said predetermined value.

* =l l= l 

1. A fluid control device comprising a body having a passage therethrough between an inlet adapted to be connected to a source of fluid under pressure and an outlet adapted to be connected to a head for discharging said fluid; a movable member normally blocking said passage and having one side exposed to fluid pressure in said passage; means including said movable member for defining a closed chamber for containing a pressurized fluid, said pressurized fluid normally forcing said movable member into said passage blocking position, said movable member adapted to move from said passage blocking position in response to the fluid pressure in said passage exceeding a predetermined value sufficient to overcome the force of said fluid in said chamber, to permit the fluid in said passage to flow to said head for discharge; and means responsive to the presence of a predetermined temperature in the vicinity of said body member to permit the escape of said fluid from said chamber and permit said movable member to be forced from said passage blocking position by the fluid in said passage, regardless of the pressure of said latter fluid.
 2. The device of claim 1 wherein said movable member is adapted to move back to said passage blocking position in response to the fluid pressure in said passage dropping below said predetermined value.
 3. A fire protection system comprising conduit means disposed in a space to be protected from fire and adapted to be connected to a source of extinguishant, a body member connected to said conduit means and having a passage therethrough between an inlet registering with said conduit means and an outlet, a discharge head connected to said outlet for discharging said fluid; a movable member normally blocking said passage and having one side exposed to said extinguishant in said passage; means including said movable member for defining a closed chamber for containing a pressurized fluid, said pressurized fluid normally forcing said movable member adapted to move from said passage blocking position in response to the force of the extinguishant pressure in said passage exceeding a predetermined value sufficient to overcome the force of said fluid in said chamber to permit the fluid in said passage to flow to said head for discharge; and means responsive to the presence of a predetermined temperature in the vicinity of said body member to permit the escape of said fluid from said chamber and thus permit said movable member to be forced from said passage blocking position by the extinguishant in said passage, regardless of the pressure of said latter fluid.
 4. The system of claim 3 wherein said movable member is adapted to move back to said passage blocking position in response to the fluid pressure in said passage dropping below said predetermined value. 